This invention relates to an orthodontic device, and more particularly, to a patient-usable device for carrying, dispensing, and installing replaceable intraoral tension-applying devices.
There are many situations in orthodontic treatment wherein it is necessary to apply tension forces between two relatively widely spaced locations in a person's mouth. These locations may either be intramaxillary (i.e., located along the same jaw). Or intermaxillary (i.e., distributed between the two jaws). An illustration of the latter kind of situation is an upper jaw overbite case in which an orthodontist decides to apply tension to pull the upper jaw rearwardly relative to the lower jaw to align them, in a fore-and-aft sense, more favorably.
It is a relatively common practice today to apply such a tension force utilizing a molded elastomer having an elongated shape with its opposite ends substantially defined by a pair of eyelets, and with an elastomeric strand extending between and joining these eyelets. In an operative condition, the eyelets are caught on hooks which have been placed by the orthodontist at the desired locations in a person's mouth, and the hooks are located so that when the device is in place, the strand between the eyelets is stretched, and thus tensed to apply the desired corrective force.
Whereas modern-day elastomeric ligatures that are used to tie an arch wire to brackets (or the like) mounted within a person's mouth, after installation, and until replacement, are relatively static in nature, tension-applying devices for the kind of purpose like that expressed above experience quite a bit of dynamic movement after installation. For example, where such a device is used in an intermaxillary setting, the device is tensed and relaxed recurrently and over widely different limits each time that a person makes a jaw movement in his mouth. Accordingly, these devices have relatively short useful life spans, and must be replaced at frequent intervals.
In the past, it has been a practice for an orthodontist to supply a patient with an extra supply of tension-applying devices like the one which he has originally installed, with instructions to replace the same at certain minimum time intervals, or whenever breakage occurs. Unfortunately, patients, who are often quite young, are not reliable replacers of expended or broken elastomer devices, and even with respect to those who are, they experience some inconvenience and difficulty in installing a new device properly.
A general object of the present invention is to facilitate patient attendance to an orthodontist's instructions to replace tension-applying devices of the type generally mentioned.
Proposed according to a preferred embodiment of the invention is a unitary apparatus having a molded portion with a body which acts as a carrier for a plurality of severably joined (integrally molded) tension-applying devices of the type generally outlined above. Each of these devices, in general terms, has an elongated configuration, with eyelets formed at opposite ends interconnected by an elastomeric strand. Included in the molded portion of the device is an elongated finger, the outer end of which carries a relatively rigid catch which can be used to facilitate placement and installation of a replacement tension-applying device in a person's mouth.
In actual operation, when it is necessary to replace a tension-applying device, a fresh one of these devices is broken away from the body of the apparatus, with an eyelet therein then caught over the catch in the device. With the apparatus held in the patient's hands, it then becomes a relatively easy proposition for him to place the opposite or free end of the severed tension-applying device at one of the hook locations in the mouth where it is intended to be hooked, with the apparatus, thereafter through pulling on the finger, used to stretch the tension-applying device into a condition enabling ready placement of the other end at the other hook location in the mouth.
A number of advantages are offered by the apparatus of the invention. To begin with, what a patient leaves an orthodontist's office with is a unitary product, rather then an aggregation of separate replacement pieces which can easily be dispersed and lost. Secondly, the apparatus of the invention is constructed to act as its own dispenser and installation tool for a tension-applying device which is severed from the main body in the apparatus. This construction greatly minimizes the specific dexterity which is required of a patient in replacing a device. Finally, the use of the main body in the apparatus, and its catch, to stretch a replacement tension-applying device into place, overcomes the difficulty which many young people have in finger-stretching a replacement device sufficiently to enable hooking of its opposite ends in place.
These and other objects and advantages which are attained by the invention will become more fully apparent as the description which now follows is read in conjunction with the accompanying drawings.